A sterile, metallic device intended to be permanently implanted around the neck of an aneurysm (a balloon-like sac formed on a blood vessel) for occlusion, to prevent it from bleeding or bursting and to isolate it from the rest of the vessel. The device is typically an alpha-shaped coil spring, with blades that open like jaws, that comes with a dedicated applier for application to the aneurysm. The device is available in a variety of sizes and its blades may be straight or curved. It is typically used to treat intracranial aneurysms; it may also be used to prevent bleeding from small blood vessels.